Check valve arrangement for use in bottoms of swimming pools

ABSTRACT

A device for preventing floating of swimming pools by allowing ground water to enter the pool when the pressure thereof is greater than the pressure in the pool includes a conical member tapering upwardly set in the bottom wall of the pool and ending a slight distance below the upper face of the finished pool bottom. Above this conical member and having its upper edge flush with the finished bottom is a check valve arrangement which includes a ring set in the concrete and having an upwardly tapering portion which ends in a very thin upper edge flush with the upper face of the concrete and having a plug portion which is hollow and likewise has a very thin upper edge. These two parts have opposed seats which can engage an O-ring. The hollow plug is filled with concrete which is the same as that used in finishing the bottom of the pool so that the device is only slightly noticeable. If ground water is present at a pressure greater than that of the water pressure in the pool, it will move upwardly through the cone and lift the plug valve so as to enter the pool.

United States Patent [1 1 Kaufman [111 3,829,910 [451 Aug. 20, 1974CHECK VALVE ARRANGEMENT FOR USE IN BOTTOMS OF SWIMMING POOLS [76]Inventor: Samuel Kaufman, 509A Wilson P1.,

Frederick, Md. 21701 [22] Filed: Jan. 4, 1973 [21] Appl. No.: 320,959

Primary Examiner-Henry K. Artis [57] ABSTRACT A device for preventingfloating of swimming pools by allowing ground water to enter the p001when the pressure thereof is greater than the pressure in the poolincludes a conical member tapering upwardly set in the bottom wall ofthe pool and ending a slight distance below the upper face of thefinished poolbottom. Above this conical member and having its upper edgeflush with the finished bottom is a check valve arrangement whichincludes a ring set in the concrete and having an upwardly taperingportion which ends in a very thin upper edge flush with the upper faceof the concrete and having a plug portion which is hollow and likewisehas a very thin upper edge. These two parts have opposed seats which canengage an O- ring. The hollow plug is filled with concrete which is thesame as that used in finishing the bottom of the pool so that the deviceis only slightly noticeable.

If ground water is present at a pressure greater than that of the waterpressure in the pool, it will move upwardly through the cone and liftthe plug valve so as to enter the pool.

4 Claims, 3 Drawing Figures CHECK VALVE ARRANGEMENT FOR USE IN BOTTOMSOF SWIMMING POOLS BACKGROUND OF THE INVENTION 1. Field of the InventionThe invention relates to check valve arrangements for the bottom ofswimming pools for preventing floating of the pool by ground water.

2. The Prior Art It has been known for many years that swimming poolsare likely to float if they are emptied when there is substantial groundwater around them. To avoid this, it has been known to place checkvalves in the bottom of the pool so that the ground water may enter thepool from below if its pressure exceeds that of the water in the pool.These arrangements have in general in the past been unsatisfactorybecause they are likely to be fouled by sand or gravel carried up by theground water, which prevents them from reseating properly when the poolis filled. Likewise, some contractors in order to save expense and laborhave omitted such check valves, even where they are required by law.This omission cannot be detected by an inspector after the pool has beenfilled, and often the owner does not know of the omission until for somereason the pool is emptied and floating takes place.

Applicant's company has had on the market for some time an improvementover this construction which utilizes an upwardly tapering cone ofsubstantially 4 inches id, at its top with a type of plug valve guidedin a seat and closing on an O-ring when the pressure in the pool exceedsthat in the ground outside. Such an arrangement works quitesatisfactorily to prevent fouling of the valve by sand, since the coneallows the upwardly coming ground water to move sufficiently slowly toallow the sand and grit to settle out of it, but it has beenobjectionable to many pool builders and owners because it is clearlyvisible in the bottom of the pool and seems to serve no useful functionas the pool drain does.

Likewise, it has had the advantage that an inspector could tell evenwhen the pool is full whether or not :such a device had been installed.

SUMMARY OF THE INVENTION The present invention provides an arrangementof the type described above which however is substantially unnoticeable,but the insertion or omission of which can readily be noted by aninspector.

According to the invention, above a conical member there is arranged aring having an annular seat for an O-ring and an upwardly taperedannular part having a very thin upper edge, together with an upwardlyopen hollow plug with another annular seat cooperating with the O-ringand having its upper part tapering likewise to a thin edge. The hollowpart of this plug can then be filled with concrete of the same mix as isbeing used in the finish coat on the bottom of the pool, so that at itsinterior will look like a part of the pool bottom. All that will bevisible is the two thin rings formed by the upper edges of the plug andthe seat member. These are hardly noticeable to the ordinary observer,yet they can be seen sufficiently so that an inspector will know thatthe device has been installed.

A further feature of the invention lies in the fact that the cone has aclosed top end with grooves in its upper and lower faces, which preventsthe entry of concrete mix or other material into the cone during theplacing ofthe concrete, after which this wall can be readily cut away soas to leave the cone open.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. I shows in cross-section a device according to the inventioninstalled in the bottom of a swimming pool;

FIG. 2 is a cross-section of the top part of the cone; and

FIG. 3 is a cross-section of the valve assembly.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings,there is shown a cone 2 of plastic material which tapers upwardly and isclosed at the top by a wall 4, in the bottom and top parts of which areprovided annular grooves 6. The bottom wall of the cone is to rest ondirt 8. A small amount of gravel 10 is placed below the bottom of thecone 2 which has a flange 12 which rests on the dirt.

Above the cone, but not directly attached to it, is a ring 14 having anupwardly extending portion 16 of tapering shape. The ring also has aninwardly extending flange 18 with an upwardly pointed rib 20 along itsinner edge. The upper edge 22 of the part 16 is very thin, for example,as little as 15 one-thousandths of an inch.

An O-ring 24 of rubber rests on the annular rib 20.

The plug 25, which is movably mounted within the ring 14, is an upwardlyhollow annular body having a bottom 26, an outwardly and upwardlysloping wall 28,

a transverse outwardly directed part 30 and another In the installationof this arrangement, the cone 2 is placed on the dirt or other basebeneath the pool, and the ring 14 with the plug 25 are placed resting onthe cone. The main portion of the concrete 42 is then poured and risesto the point indicated by-the broken line 44, thus holding the ring 14in position. The annular position of the ring 14 can be adjusted so thatits upper edge is properly placed with relation to the level of thebottom of the pool. The finish layer 46 of concrete is then applied andis brought flush with the upper edge 22 of the ring 14.

Meanwhile, the plug 25 is filled as indicated at 40 with concrete havingthe same mix as that of the finish layer of the pool, so as to have theappearance of being a continuation of the floor of the pool. This isalso brought up flush to the upper edge 34. The top wall 4 of the coneis now cut away, and removed, and the plug 25 is placed in positionwithin the flange 16.

With this arrangement there is only a very small area exposed of theparts constituting the plug valve, whereas on the other hand it ispossible for these to be seen by a careful inspection so that theinspector will know whether such equipment has been installed.

The cone substantially prevents the rising of sand or gravel through thedevice, so that choking or fouling of the valve is substantiallyprevented.

The ring 38 serves, when the plug 25 is filled with concrete, to preventthe concrete from dropping out if the plug is removed for any purpose.

If ground water is present at a pressure greater than that of the waterpressure in the pool, it will move upwardly through the cone and liftthe plug valve so as to enter the pool.

I claim:

11 A check valve arrangement for installation in the bottom of swimmingpools comprising an annular member having an upwardly extending partwith a thin upper edge and having an upwardly directed seating surfacewithin such upwardly extending part, and an upwardly open hollow plugmember having an upwardly extending part with a thin upper edge withinand slightly spaced from the inner edge of the upwardly extending partof the annular member and having a downwardly directed seating surfaceopposite the seating surface of the ring, whereby when an O-ring isinserted between such parts it is engaged by the upwardly and downwardlydirected seating surfaces and the upper edges of the two members aresubstantially at the same level, and whereby filling of the hollow plugwith material of the same appearance as that used for the finish surfaceof the pool bottom will render the arrangement inconspicuous.

2. In combination with a valve arrangement as claimed in claim 1, anupwardly tapering downwardly open cone having at its top an outerdiameter greater than the interior diameter of said annular seat part.

3. An arrangement as claimed in claim 2, in which said cone has a wallclosing its upper end and lines of weakness around and adjacent the saidouter edge of said wall to permit the cutting out of such wall afterinstallation.

4. In a swimming pool having a concrete bottom resting on a base, aninwardly and upwardly open cone which tapers upwardly resting on suchbase and enclosed in the concrete, and a valve arrangement as claimed inclaim 1 located above said cone and having the opening in said annularmember in communication with the opening in the cone, and an O-ringbetween said seating surfaces, said upper edges of the two members beingflush with the upper face of the pool bottom and said plug member beingfilled with concrete at least a top layer of which is of the same mix asthat of such

1. A check valve arrangement for installation in the bottom of swimmingpools comprising an annular member having an upwardly extending partwith a thin upper edge and having an upwardly directed seating surfacewithin such upwardly extending part, and an upwardly open hollow plugmember having an upwardly extending part with a thin upper edge withinand slightly spaced from the inner edge of the upwardly extending partof the annular member and having a downwardly directed seating surfaceopposite the seating surface of the ring, whereby when an O-ring isinserted between such parts it is engaged by the upwardly and downwardlydirected seating surfaces and the upper edges of the two members aresubstantially at the same level, and whereby filling of the hollow plugwith material of the same appearance as that used for the finish surfaceof the pool bottom will render the arrangement inconspicuous.
 2. Incombination with a valve arrangement as claimed in claim 1, an upwardlytapering downwardly open cone having at its top an outer diametergreater than the interior diameter of said annular seat part.
 3. Anarrangement as claimed in claim 2, in which said cone has a wall closingits upper end and lines of weakness around and adjacent the said outeredge of said wall to permit the cutting out of such wall afterinstallation.
 4. In a swimming pool having a concrete bottom resting ona base, an inwardly and upwardly open cone which tapers upwardly restingon such base and enclosed in the concrete, and a valve arrangement asclaimed in claim 1 located above said cone and having the opening insaid annular member in communication with the opening in the cone, andan O-ring between said seating surfaces, said upper edges of the twomembers being flush with the upper face of the pool bottom and said plugmember being filled with concrete at least a top layer of which is ofthe same mix as that of such upper surface.